Systems and apparatus for object detection using optical sensing

A wearable device comprising:

• a housing;
• a cover material coupled to the housing, the cover material comprising a glass cover substrate of the wearable device;
• a crown at least partially external to the housing;
• an optical proximity sensor positioned within the housing of the wearable device, disposed under the cover material, and configured with a field of view including the crown at least partially external to the housing or an area above the crown, the optical proximity sensor comprising a first light emitter, a second light emitter, and one or more light detectors;
• and
• a processor coupled to the optical proximity sensor;
• wherein the one or more light detectors comprises a first light detector aligned with the first light emitter and the second light emitter in a first direction, the first light detector configured to receive a first amount of light from the first light emitter and configured to receive a second amount of light from the second light emitter;
• the first light emitter of the optical proximity sensor is configured to emit a first light path beginning within a threshold angle of a first angle and the cover material is configured to refract the first light path to a second angle, different from the first angle;
• the second light emitter is configured to emit a second light path beginning within a threshold angle of a third angle and the cover material is configured to refract the second light path to a fourth angle, different from the third angle;
• wherein the processor is configured to:
• estimate a presence of an object touching or within a threshold distance from the crown;
• or
• estimate a distance between the object touching or within the threshold distance from the crown;
• and
• wherein the processor is further configured to determine a distance of an object to the optical proximity sensor or to the crown in a second direction, different than the first direction, based on the first amount of light and the second amount of light.